D22 air conditioning resistor

[Gedibundy]

Hi I’ve just replaced my air conditioner resistor for the second time and just wondering if anyone knows what might cause the resistor to malfunction and make it only work on the level four fan.
regards G

 

[Old.Tony]

Welcome to the forum.

You're not alone with the problem - happens with the D40s too. On mine, a resistor got too hot ... burned out and it was all over except for fan speed 4. I bought a replacement off eBay (ages ago now) and it's been right as rain ever since, and it's always running when we're in the car.

I have wondered if additional drag on the fan may cause more current to flow through those resistors which will undoubtedly heat them up. If there's debris in the fan area, or perhaps even just a combination of moisture and dust, you'd think the motor would have to work harder to maintain fan speed.

 

[Gedibundy]

Welcome to the forum.

You're not alone with the problem - happens with the D40s too. On mine, a resistor got too hot ... burned out and it was all over except for fan speed 4. I bought a replacement off eBay (ages ago now) and it's been right as rain ever since, and it's always running when we're in the car.

I have wondered if additional drag on the fan may cause more current to flow through those resistors which will undoubtedly heat them up. If there's debris in the fan area, or perhaps even just a combination of moisture and dust, you'd think the motor would have to work harder to maintain fan speed.

I was having some trouble with the fan belts and the air con earlier. I wonder if that triggered the spikes to cause the resistor to break. I've tried even fixing the tracks on the resistor though it didn't work. I managed to find one on Ebay too. $20. I bought a spare too just in case. I've had the fan belts replaced so hopefully that stops the problem.

 

[tweak'e]

one of the problems with the D22 is no air con filter so the heater tends to get clogged up reducing airflow. low air flow and especially high outside air temp means the resistor pack could overheat. especially if fan gets fouled up or bad bearings in the fan. the more load on the fan the more current they draw, which means more heat in the resistor pack.

 

[Gedibundy]

Ok, I've got it booked in for a service, I'll get the guy to check out the fan. It's looks like a pain to get at.

 

[gazza414]

How did you get on with the replacement..mine has just failed again too..ie 2nd one was aftermarket and lasted about 1-2 years

 

[johnl56]

Just replaced mine as well. What a utter PITA to get to the back screw. Decided to leave it out just in case. Mine was just corroded so age was the big issue, probably the original.